With the 22V transformer, you get 26.4V plus U use CRCRCRC power supply. With the 3pc R you burn up some power also. I hope you not using any high-value resistors there to burn up more power. Your 25.6V is absolutely normal with your setup.
When you buy a transformer to regular Class A bias calculation(not talking about Alep X where the total bias is over 7A per channel) 22ACV x 1.2 under load =26.4V DC.
I am using 0.15R - ok so normal. My problem is that I have been using 1.4x and subtracting 3-4v for load. But 1.2x multiplier seems way to go for Class A. My CRCRCRC burns off 1.2v.
B.B. one channel: 39,7vdc under load. 2x30vac sec 545va trafo. Can't remember or measure Alpha20 right now..
Oh, forgot that CCRCCRC where 0.2ohm per resistor.
Hi X?...
I recently bought a pair of 22VAC 300VA Anteks, hoping to get a solid 27vdc under load of 1.6amps. After the CRCRCRC, I am getting 25.6v. This is for a high output variant of the Alpha 20 that I am testing - just seeing if pushing higher voltage and increased cooling via CPU coolers and fans can work to boost power output.
Antek supplier specifies output voltage under specific load current (not much data though) with 120vac input. In my area line voltage from provider can vary from 115 to 122vac (I have a real time indicator) in normal situation (not too cold/hot weather). Mostly depends on time of the day with demands from all houses/buildings.
Also, rectifier diodes have different voltage drop depending on their temperature. Check the specific data sheet of your diodes.
And then you add the voltage drop of the resistors in series in your PSU.
Fab
With my 600va, 32v transformers, my BB’s are running at 37.5vdc with a CRCLC. If I use a capMx instead of the CRCLC the voltage increases to 38vdc.
Since it’s summertime, my line voltage varies widely during a 24 hr period. Anywhere from 112vac to 125vac.
I think my ALPHA20 is running 23vdc, I’d have to check (don’t remember).
I did notice that the DC offset increased from 10mv @36vdc to 25mv @37.5vdc?
Since it’s summertime, my line voltage varies widely during a 24 hr period. Anywhere from 112vac to 125vac.
I think my ALPHA20 is running 23vdc, I’d have to check (don’t remember).
I did notice that the DC offset increased from 10mv @36vdc to 25mv @37.5vdc?
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You have these 99dB Klipsch speakers so would never know what 70w feels like on the B.B.
Exactly X
My Forte’s play incredibly loud with the ALPHA20. The appeal about the BB is that I get to use a powerful Class A amp with much less efficient speakers that I have.
This looks like a nice case for an all fan-cooled Alpha. Very IT looking but nice airflow grill holes and built in flow thru fans (which I will drop the speed on).
Amazon.com: Rosewill 4U Server Chassis / Server Case / Rackmount Case, Metal Rack Mount Computer Case with 8 Bays & 4 Fans Pre-Installed (RSV-R4000): Computers & Accessories
Amazon.com: Rosewill 4U Server Chassis / Server Case / Rackmount Case, Metal Rack Mount Computer Case with 8 Bays & 4 Fans Pre-Installed (RSV-R4000): Computers & Accessories
X, I have another song for listening tests. I haven't been able to find a CD yet, but in the mean time check on YT, this performance is amazing.
Ennio Morricone's 1966 main theme for the "Good, Bad, and Ugly" performed by the Danish National Symphony Orchestra in a live performance earlier this year. Better than the original.
Enjoy,
David
Ennio Morricone's 1966 main theme for the "Good, Bad, and Ugly" performed by the Danish National Symphony Orchestra in a live performance earlier this year. Better than the original.
Enjoy,
David
X, I have another song for listening tests. I haven't been able to find a CD yet, but in the mean time check on YT, this performance is amazing.
Ennio Morricone's 1966 main theme for the "Good, Bad, and Ugly" performed by the Danish National Symphony Orchestra in a live performance earlier this year. Better than the original.
Enjoy,
David
Superb recording and rendition! Makes me want to watch the movie again.
Thanks for the tip!
Yes, terrific rendition!
It is interesting watching Morricone conducting a large orchestra; he is the composer equivalent of Umberto Eco, an aesthete, and an intellectual. No one can evoke emotion in music scores like Morricone, he is better than Zimmer.
Thanks Drpro, good link......
Hugh
It is interesting watching Morricone conducting a large orchestra; he is the composer equivalent of Umberto Eco, an aesthete, and an intellectual. No one can evoke emotion in music scores like Morricone, he is better than Zimmer.
Thanks Drpro, good link......
Hugh
The speakerlab where Alpha B.B. was playing is now under renovation. I had a basement flooding over the weekend and dealing with cleanup. All amplifiers were ok but I lost several foam core speakers. It will be a while before back up and running. I do miss listening to this amp. All wet carpeting pulled out and now in process of drying. Things will be a bit quiet on DIY front for a while.
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